The present invention relates to a dispenser for dispensing a stick of product, for example, a lipstick, a stick of foundation, a stick of treatment composition, or a stick of moisturizing composition. The dispenser of the present invention is particularly suited for use with sticks of product containing highly volatile solvents (e.g., silicones). For example, such solvents are commonly used in lipsticks.
In conventional dispensers, sticks of product are packaged in a cylindrical tube containing a platform. The platform is generally configured to support a stick of product and to move axially within the tube in response to an actuating input, between a product storage position and a product application position. A mechanism is provided to control movement of the platform within the tube. For example, conventional dispensers sometimes use a mechanism including a threaded rod positioned under the platform and a wheel attached to the rod, wherein the wheel is rotated to move the rod and platform within the tube. Conventional dispensers also sometimes use a helical ramp formed in a wall of the tube to facilitate movement of the platform. A cover is generally provided on the cylindrical tube to seal the tube and thereby prevent the product from drying out.
Although some conventional product-stick dispensers are relatively reliable, they sometimes suffer from problems associated with pressure xe2x80x9cbuild upxe2x80x9d in the cylindrical tube. When the cover is positioned on the tube to seal off the tube from outside air, pressure in a portion of the tube above the platform sometimes increases above atmospheric pressure. The increased pressure is sometimes caused when the engagement of the cover on the tube compresses air in the tube. Increased pressure also results from increased temperature in the tube, for example, when the dispenser is left in direct sunlight. Regardless of the way in which increased pressure is generated in a dispenser, this phenomenon is hereinafter referred to as xe2x80x9cexcessive pressure.xe2x80x9d
In conventional dispensers, excessive pressure in the tube occasionally reaches a level that can cause the cover to unseal from the tube. If a cover is left unsealed for even a short time, a product stick including a highly volatile solvent (such as lipstick) can dry out and become unusable. Dispensers having a cover that provides a very tight seal over the tube can limit the occurrence of cover unsealing, but consumers prefer a dispenser having a cover that can be easily removed from the tube. Conventional dispensers have failed to satisfy the need for a dispenser having a cover that is easy to remove, but that remains on the tube, even when the tube experiences an excessive pressure condition caused by replacing the cover on the tube or increasing the temperature inside the tube.
In light of the foregoing, there is a need in the art for an improved dispenser for dispensing a stick of product.
Accordingly, the present invention is directed to dispensers and methods of applying a stick of product using dispensers that obviate one or more of the short-comings of the related art.
A preferred object of the invention is to provide a dispenser for the sealed packaging and dispensing of a stick of product that is simple and inexpensive to produce, while still providing a reliable seal for the dispenser and stick of product.
It should be understood that the invention could still be practiced without performing one or more of the preferred objects and/or advantages set forth above. Still other objects will become apparent after reading the following description of the invention.
To achieve these and other advantages, and in accordance with the purposes of the invention, as embodied and broadly described herein, the invention includes a dispenser for dispensing a stick of product including a holder configured to hold the stick of product and a housing containing the holder. The housing has a first end, a second end, and an opening in the first end. The housing is configured to move the holder in a first direction toward the opening to allow dispensing of the product and in a second direction away from the opening to allow storage of the product. The dispenser further includes a removable closure configured to sealably close the opening during storage of the product. A sealing member is provided for sealing at least a portion of the housing between the holder and the opening from at least a portion of the housing between the holder and the second end. The dispenser also includes an elastic member between the holder and the second end of the housing. The elastic member is configured to deform and thereby allow for movement of the holder in the second direction when excessive pressure is formed between the holder and the opening.
In another aspect, the housing includes a first section and a second section rotatable with respect to one another. The first and second sections are preferably configured so that rotation of the first section in one direction moves the holder in the first direction and rotation of the first section in an opposite direction moves the holder in the second direction.
The elastic member preferably allows the holder to move toward the second end of the housing to absorb at least a portion of excessive pressure between the holder and the opening. By limiting the amount of excessive pressure, the elastic member enables the closure to reliably seal the opening in the first end of the housing while permitting a user to easily remove the closure from the housing during use of the dispenser.
In one embodiment, the sealing member is a sealing lip on an edge of the holder. In another embodiment, the sealing member is an O-ring or any other type of structure that provides a seal between two elements that move with respect to one another. The sealing member preferably seals the stick of product from at least a portion of the housing between the holder and the second end that is not sealed from outside air. When the closure seals the opening on the housing, the stick of product is preferably sealed from outside air and contaminants that dry out the product.
Preferably, the elastic member includes a block of foam and/or an elastomeric material that is deformable. When the elastic member includes the block of foam, the block of foam preferably is chosen from at least one of polyvinyl chloride foam, polyurethane foam, polyether foam, synthetic rubber foam (e.g., SBR), and natural rubber foam (e.g., NBR). When the elastic member includes the elastomeric material, the elastomeric material is preferable chosen from at least one of silicone elastomers, nitrile elastomers and an elastomeric material sold under the brand name Polynorbordene(copyright). In an alternate embodiment, the elastic member is a spring, for example, a helical spring. In still another embodiment, the elastic member has the shape of a bellows. Many other types of elastic members are also within the scope of the present invention.
The dispenser may include a sealing element configured to cooperate with the removable closure to sealably close the opening during storage of the product. Optionally, the closure may include a sealing element configured to sealably close the opening. Optionally, the closure includes a thermoplastic insert that seals the opening in the first end of the housing from outside air.
Preferably, the housing includes a sleeve configured to contain the holder and an actuating member coupled to the sleeve so that the actuating member is capable of rotating relative to the sleeve.
The dispenser preferably includes a threaded member coupled to the holder and a receiving member having threads configured to engage the threads of the threaded member. Preferably, the holder moves in the first direction and in the second direction when the receiving member is rotated relative to the threaded member. Preferably, the threaded member is a rod and the receiving member is a nut. In the alternative, the movement of the holder is achieved by a helical-ramp mechanism, like those included on conventional dispensers, such as lipstick dispensers.
Preferably, the receiving member is coupled to the actuating member to preclude relative rotation therebetween. The threaded member is preferably coupled to the sleeve to preclude relative rotation therebetween. In one embodiment, the threaded member has a non-circular cross-section (e.g., a threaded rod having two flat sides over at least part of its length) and is coupled to the sleeve by a guiding member of corresponding cross-section. In the alternative, when the sealing member is an O-ring, the sealing member may couple the threaded member to the sleeve by friction, thereby preventing relative rotation therebetween.
In yet another embodiment, the receiving member is a nut that is supported by the elastic member. A first end of the elastic member preferably supports the nut and a second end of the elastic member is preferably on a bottom portion of the actuating member. By way of example, the elastic member may contact a bottom portion of the actuating member or it may contact a stopping member on the actuating member. Preferably, the elastic member and the receiving member are integral, for example, they are a single-piece formed by thermoplastic molding.
Preferably, the holder includes a vent near a lower portion of the holder. The vent preferably allows air to flow out of the holder when a stick of product is positioned on the holder.
The dispenser is preferably used for the dispensing of a lipstick, a stick of foundation, and a stick of treatment and/or moisturizing composition.
In another aspect, the invention includes a dispenser for dispensing a stick of product including a housing having a first portion and a second portion coupled together so that the first and second portions are rotatable with respect to one another. A removable closure is configured to sealably close an opening in the second portion of the housing. A holder configured to hold a stick of product is also provided. The holder is in the housing and is coupled to the housing so that rotation of the first portion with respect to the second portion provides dispensing movement of the holder toward the opening and storage movement of the holder away from the opening. An elastic member positioned in the housing is coupled to the holder so that excessive pressure in the housing causes deformation of the elastic member to allow pressure absorption movement of the holder, with respect to the first and second portions, in a direction away from the opening.
In still another aspect, the invention includes a method of limiting excessive pressure in a dispenser similar to the dispensers described above. The method includes removing the closure from the housing. The product is then applied to a surface. After applying the product, the closure is replaced on the housing to sealably close the opening. As excessive pressure develops between the holder and the opening, the elastic member is deformed to thereby absorb at least a portion of the excessive pressure.
In a further aspect, the method includes moving the holder axially within the housing after the closure is removed to expose the stick of product from the housing and then moving the holder axially within the housing to store the stick of product after applying the product to the surface.
Besides the structural arrangements set forth above, the invention could include a number of other arrangements, such as those explained hereinafter. It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.